The U.K.'s rapidly approaching plan to leave the European Union has many automakers anxious, especially those whose primary manufacturing facilities are in the U.K. itself. European Union member states can trade with each other freely, i.e., without any tariffs or quotas.

He said that the firm urgently needs "greater certainty" to continue to investing heavily in the UK. Without that certainty it will become increasingly more hard to invest heavily in the UK, Dr. Speth warned.

May is under increasing pressure from European Union officials, companies and some lawmakers to move faster with the negotiations to leave the European Union, a departure that will be Britain's biggest trading and foreign policy shift in half a century.

'This would be in jeopardy should we be faced with the wrong outcome.

"For more than 250 years, since the era of Adam Smith, Britain has championed free markets and made the case for free trade".

"The recent statement from JLR only reaffirms this position that a Brexit which increases bureaucracy, reduces productivity and competitiveness of the UK Industry is in no-one's interest".

It employs 40,000 people directly and 260,000 work in its supply chain.

- It is the UK's largest auto manufacturer, employer, and investor.

In 2017, the company sold 621,000 cars, with 80 per cent of them going to 130 countries.

New Land Rover cars are seen in a parking lot at the Jaguar Land Rover plant at Halewood in Liverpool, northern England. Eighty percent of the company's production went to 130 countries.

Until the latest comments JLR, owned by India's Tata Motors, had been the exception in the United Kingdom auto industry in being outwardly quite relaxed about the prospect of Britain's departure from the European Union in 2019, although it had raised it as a potential challenge in company report.

But the company had also revealed plans to invest in the Solihull site to allow it to build its new Range Rover models, some of which will be electric-powered, from 2020.

- Jaguar pays more than £2 billion in tax each year. 20% went to Europe.

Len McCluskey, general secretary of the UK's biggest union Unite, called on the government to stop playing "Russian roulette" with people's jobs and livelihoods.